The present invention generally relates to the field of light emitting diode (LED), and in particular to an LED structure allowing for projecting light in a sideway direction.
Light emitting diodes (LEDs) are commonly used in electronic industry for a variety of applications, among which light source is one of the most common applications of the LEDs. Conventionally, the LEDs are mounted on a circuit board to project light in a direction substantially normal to the circuit board. FIG. 11 of the attached drawings shows an example of the conventional LEDs, wherein the LED comprises a substrate from which two terminals extend. A chip is mounted to one of the terminals and is connected to another terminal by a lead. The terminals are mounted to a circuit board and are electrically connected to conductor patterns of the circuit board to supply electrical power to the LED. The terminals are mounted to the circuit board in a standing manner with the chip facing away from the circuit board. Thus, the light emitted from the LED is directed away from the circuit board in a direction substantially normal to the circuit board.
FIG. 12 of the attached drawings shows a modification of the conventional LED, wherein a heat dissipater plate is mounted to one of the terminals of the LED for enhancing heat dissipation of the LED. Similarly, the light emitted from the LED is directed upward away from the circuit board. Thus, the light can only be projected away from the circuit board in a direction substantially normal to the circuit board.
As a consequence, such conventional LEDs cannot be used in applications whereby light projected in a sideway direction with respect to a circuit board is required. In addition, the heat dissipater plate of the conventional LED is mounted to the terminal between the LED and the circuit board. Further increasing the size of the heat dissipater plate can only be done in a transverse direction. This may cause undesired interference with other parts or may be further constrained by the other parts. Thus, increasing the size of the heat dissipater plate in order to enhance the heat dissipation is in general very difficult in the conventional LEDs.
FIGS. 13 and 14 show two examples of conventional LEDs that allow for sideway projection of the light emitted from the LEDs. The LEDs comprise terminals extending in a direction substantially normal to the light projection direction of the LEDs. Thus, when the terminals are mounted to a circuit board in a standing manner, the light emitted from the LEDs is projected in a sideway direction with respect to the circuit board. However, no heat dissipation means can be formed with the LEDs for enhanced heat dissipation, which in turn allows for increase of power consumption of the LEDs. Thus, the performance of the LEDs in emitting high power light is subject to limitation.
It is thus desired to provide a sideway-projecting light emitting diode structure for overcoming the above problems.
An object of the present invention is to provide a sideway-projecting light emitting diode that allows light emitted from the light emitting diode to be projected in a sideway direction with respect to a circuit board to which the light emitting diode is mounted.
Another object of the present invention is to provide a sideway-projecting light emitting diode structure comprising a heat dissipation member of different shapes and sizes for providing excellent and optimum heat dissipation to the light emitting diode in order to improve the overall performance of the light emitting diode.
To achieve the above objects, in accordance with the present invention, there is provided a sideway-projecting light emitting diode (LED) comprising an enclosure made of a light-transmitting material having first and second opposite side faces. The first side face forms a light-focusing portion. First and second conductive terminals are fixed in the enclosure and have tails extending beyond the second side face. A support member made of conductive materials has an inner end fixed in the enclosure between the first and second terminals and a remote end extending beyond the side face. A bowl is formed on the inner end of the support member for receiving and retaining a chip substantially confronting the light-focusing portion and electrically connected to the first and second terminals. A heat dissipation plate is mounted to the remote end of the support member for enhancing heat dissipation of the light emitting diode which in turn allows for increased power consumption of the light emitting diode and increased brightness of the light emitted from the light emitting diode. By edge-mounting the light emitting diode to an edge of a circuit board with the tails of the terminals soldered to the circuit board, light emitted from the chip is allowed to project through the light-focusing portion in a sideway direction with respect to the circuit board.